U.S. patent application number 14/917489 was filed with the patent office on 2016-07-28 for bar material supplying device and numerical control machine tool having the same.
The applicant listed for this patent is CITIZEN HOLDINGS CO., LTD., CITIZEN MACHINERY CO., LTD.. Invention is credited to Yutaka SHIBUI, Kiyohiko WATANABE.
Application Number | 20160214179 14/917489 |
Document ID | / |
Family ID | 52688735 |
Filed Date | 2016-07-28 |
United States Patent
Application |
20160214179 |
Kind Code |
A1 |
WATANABE; Kiyohiko ; et
al. |
July 28, 2016 |
BAR MATERIAL SUPPLYING DEVICE AND NUMERICAL CONTROL MACHINE TOOL
HAVING THE SAME
Abstract
A bar material supplying device includes a feed rod having a
leading end provided with a finger chuck, a feed rod servomotor and
an air cylinder device that move the feed rod in a longitudinal
direction to insert and pull the bar material into and from the
finger chuck, and an NC device that controls driving of the feed
rod servomotor and driving of the air cylinder device. The NC
device controls the driving of the feed rod servomotor and the
driving of the air cylinder device to move the feed rod in an
operation of inserting and pulling the bar material into and from
the finger chuck, and operates as an error allowable device that
allows an error of an operation amount of the feed rod servomotor
motor in the operation of inserting and pulling the bar material
into and from the finger chuck.
Inventors: |
WATANABE; Kiyohiko;
(Iruma-shi, Saitama, JP) ; SHIBUI; Yutaka;
(Kawagoe-shi, Saitama, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
CITIZEN MACHINERY CO., LTD.
CITIZEN HOLDINGS CO., LTD. |
Kitasaku-gun, Nagano
Tokyo |
|
JP
JP |
|
|
Family ID: |
52688735 |
Appl. No.: |
14/917489 |
Filed: |
September 8, 2014 |
PCT Filed: |
September 8, 2014 |
PCT NO: |
PCT/JP2014/073645 |
371 Date: |
March 8, 2016 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
B23Q 2707/003 20130101;
B23B 13/123 20130101; B23B 13/021 20130101; B23B 13/022 20130101;
B23B 13/125 20130101; B23Q 2005/005 20130101; B23Q 7/042 20130101;
B23B 7/02 20130101 |
International
Class: |
B23B 13/02 20060101
B23B013/02 |
Foreign Application Data
Date |
Code |
Application Number |
Sep 18, 2013 |
JP |
2013-192718 |
Claims
1. A bar material supplying device comprising: a feed rod having a
leading end provided with a finger chuck that insertably and
detachably holds a bar material; a motor and a cylinder device that
move the feed rod in a longitudinal direction to insert and pull
the bar material into and from the finger chuck; and a control
device that controls driving of the motor and driving of the
cylinder device, wherein the control device controls the driving of
the motor and the driving of the cylinder device to move the feed
rod in an operation of inserting and pulling the bar material into
and from the finger chuck, and operates as an error allowable
device that allows an error of an operation amount of the motor in
the operation of inserting and pulling the bar material into and
from the finger chuck.
2. The bar material supplying device according to claim 1, wherein
the error allowable device sets an allowable range of the error of
the operation amount of the motor to be larger than an allowable
range of an error of an operation amount in an operation except the
operation of inserting and pulling the bar material into and from
the finger chuck.
3. The bar material supplying device according to claim 1, wherein
the error allowable device is provided with a current controller
that controls driving current of the motor.
4. The bar material supplying device according to claim 1, wherein
the cylinder device does not drive the feed rod in an operation
except the operation of inserting and pulling the bar material into
and from the finger chuck.
5. The bar material supplying device according to claim 1 further
comprising a memory that stores an allowable range corresponding to
the operation of inserting and pulling the bar material into and
from the finger chuck and an allowable range corresponding to an
operation except the operation of inserting and pulling the bar
material into and from the finger chuck, wherein the control device
selects the allowable range corresponding to the operation of
inserting and pulling the bar material into and from the finger
chuck of the memory when inserting and pulling the bar material
into and from the finger chuck, and selects the allowable range
corresponding to the operation except the operation of inserting
and pulling the feed rod into and from the finger chuck of the
memory in the operation except the operation of inserting and
pulling the bar material into and from the finger chuck to
determine the error of the operation amount of the motor.
6. The bar material supplying device according to claim 1, wherein
the control device sets a size of the allowable range according to
a command code of the operation to the bar material supplying
device that corresponds to the operation of inserting and pulling
the bar material into and from the finger chuck.
7. A numerical control machine tool including the bar material
supplying device according to claim 1.
Description
TECHNICAL FIELD
[0001] This invention is related to a bar material supplying device
and a numerical control (NC) machine tool (hereinafter referred to
as an NC machine tool) having the same.
BACKGROUND ART
[0002] A bar material supplying device supplies a bar material as a
working target to an NC machine tool. The bar material supplying
device is placed behind the NC machine tool. The bar material
supplying device includes a feed rod having a leading end provided
with a finger chuck and a motor for driving the feed rod back and
forth. In the bar material supplying device, when the feed rod is
driven forward, the back end portion of the fixed bar material is
inserted into the finger chuck to be chucked by the finger chuck
(Patent Literature 1). In the bar material supplying device, the
position of the bar material chucked by the finger chuck is fixed,
and the bar material is released from the figure chuck by moving
the feed rod backward. A control device controls the driving of the
motor.
CITATION LIST
Patent Literature
[0003] Patent Literature 1: Japanese Laid Open Patent No.
H08-276303
SUMMARY
Technical Problem
[0004] When chucking a thick bar material having a diameter of 40
mm or more, for example, in the bar material supplying device, the
bar material may not be inserted into the finger chuck due to the
shortage of the driving force of the motor. The present invention
has been made in view of the above circumference, and an object of
the present invention is to provide a bar material supplying device
capable of chucking a bar material even when driving force of a
motor is insufficient and also an NC machine tool including the bar
material supplying device.
Solution to Problem
[0005] A bar material supplying device according to the present
invention includes a feed rod having a leading end provided with a
finger chuck that insertably and detachably holds a bar material, a
motor and a cylinder device that move the feed rod in a
longitudinal direction to insert and pull the bar material into and
from the finger chuck, and a control device that controls driving
of the motor and driving of the cylinder device, wherein the
control device controls the driving of the motor and the driving of
the cylinder device to move the feed rod in an operation of
inserting and pulling the bar material into and from the finger
chuck, and operates as an error allowable device that allows an
error of an operation amount of the motor in the operation of
inserting and pulling the bar material into and from the finger
chuck. An NC machine tool having the bar material supplying device
according to the present invention is an NC machine tool including
the bar material supplying device according to the present
invention.
Advantageous Effects
[0006] According to the bar material supplying device and the NC
machine tool including the bar material supplying device of the
present invention, the feed rod is driven by both of the motor and
the cylinder device, so that the bar material can be inserted into
the finger chuck by adding the driving force of the cylinder device
even when the driving force of the motor is insufficient. Moreover,
in the bar material supplying device and the NC machine tool
including the bar material supplying device, the error of the
control of the motor can be prevented and controlled by the error
allowable device even when the error of the operation amount of the
motor is larger than the allowable range of the error of the
operation amount in an operation except the operation of inserting
and pulling the bar material into and from the finger chuck due to
the operation of the cylinder device when the bar material is
inserted and pulled into and from the finger chuck.
BRIEF DESCRIPTION OF DRAWINGS
[0007] FIG. 1 is a view showing an automatic lathe as one example
of an NC machine tool having a bar material supplying device
according to the present invention.
[0008] FIG. 2 is a schematic view showing the details of the
automatic lathe shown in FIG. 1.
[0009] FIG. 3 is a view showing control of a main spindle
servomotor, a feed rod servomotor, and an air cylinder device by an
NC device.
[0010] FIG. 4 is a view showing a configuration of the NC
device.
DESCRIPTION OF EMBODIMENT
[0011] An embodiment of a bar material supplying device and an NC
machine tool having the bar material supplying device according to
the present invention will be described with reference to the
drawings.
[0012] An automatic lathe 100 of the present embodiment includes an
automatic lathe main body 10, a bar material supplying device 50
that supplies a bar material 200 to the automatic lathe main body
10, and an NC device 90 that numerically controls the operation of
the automatic lathe main body 10 and the bar material supplying
device 50, as shown in FIG. 1.
[0013] The automatic lathe main body 10 includes a main spindle 20
that supports the bar material 200 to rotate about an axis and
moves along the axis direction, a main spindle servomotor 30 that
moves the main spindle 20 in the axis direction by rotating a ball
screw 31, and a tool post 40 on which a tool for working the bar
material 200 is held, as shown in FIG. 2. The main spindle
servomotor 30 is driven based on a command of the NC device 90, as
shown in FIG. 3.
[0014] The bar material supplying device 50 includes a base 52
extending in a longitudinal direction and two legs 51 and 51 that
horizontally support the base 52. The bar material supplying device
50 is placed behind the automatic lathe main body 10 in alignment
with the main spindle 20. The bar material supplying device 50
stocks many bar materials 200, and automatically supplies the
stocked bar materials 200 one by one to the automatic lathe main
body 10. The base 52 includes inside thereof a feed rod 60 that
pushes and pulls the bar material 200 in the longitudinal direction
along the base 52, a chain 71 that is connected to the feed rod 60
through a connection member 62 and is circularly provided along the
longitudinal direction, and a feed rod servomotor 74 and an air
cylinder device 80 that drive the chain 71 in the longitudinal
direction.
[0015] The feed rod servomotor 74 and the air cylinder device 80
are driven based on the command of the NC device 90. A finger chuck
61 is provided in the front end of the feed rod 60. The finger
chuck 61 has a cylinder with the longitudinal direction of the feed
rod 60 as an axis. A plurality of slots each of which extends in
the axis direction is formed in a circumference wall of the
cylinder. The bar material 200 having a diameter larger than the
inner diameter of the cylinder is inserted into the cylinder by
opening the slots while elastically deforming the circumference
wall outward, so that the bar material 200 is chucked.
[0016] The chain 71 is wound around a driving sprocket 72 that is
disposed in the front and is connected to the feed rod servomotor
74 and a driven sprocket 73 that is disposed in the back, and is
driven back and forth along the rotation of the driving sprocket
72. The chain 71 is connected to the air cylinder device 80 through
a connection member 63.
[0017] The air cylinder device 80 drives the chain 71 forward along
with the feed rod servomotor 74 when the finger chuck 61 chucks the
bar material 200. The air cylinder device 80 drives the chain 71
backward along with the feed rod servomotor 74 when the finger
chuck 61 releases the bar material 200.
[0018] Upon the driving of the feed rod servomotor 74, the driving
sprocket 72 rotates, and the chain 71 is driven forward or backward
according to the rotation direction of the feed rod servomotor 74.
The air cylinder device 80 drives the chain 71 back and forth when
the air cylinder device 80 is connected to the chain 71 while the
air cylinder device 80 does not drive the chain 71 when the air
cylinder device 80 is disconnected from the chain 71. When chucking
the bar material 200 by the finger chuck 61, the air cylinder
device 80 is connected to the chain 71 to drive the chain 71
forward along with the feed rod servomotor 74 while the bar
material 200 is fixed on the base 52 by a not-shown fixing member
such as a stopper. By adding the driving force of the air cylinder
device 80 to the driving force of the feed rod servomotor 74, even
when the bar material 200 has a diameter of 40 mm or more, for
example, the feed rod 60 moves forward against the frictional force
between the finger chuck 61 and the bar material 200 and the
elastic force (fitting resistance force) that opens the slits, and
the back end of the bar material 200 is inserted into the finger
chuck 61. The bar material 200 is thereby chucked by the finger
chuck 61.
[0019] After chucking the bar material 200, the fixation of the bar
material 200 by the fixing member is released, the chain 71 is
disconnected from the air cylinder device 80, and the chain 71 is
driven only by the feed rod servomotor 74. The bar material 200 is
supplied to the automatic lathe main body 10 by moving the feed rod
60 forward or the bar material 200 is collected from the automatic
lathe main body 10 by moving the feed rod 60 backward.
[0020] When releasing the collected bar material 200 from the
finger chuck 61, the air cylinder device 80 is connected to the
chain 71 to drive the chain 71 backward along with the feed rod
servomotor 74 while the bar material 200 is fixed on the base 52 by
the fixing member. By adding the driving force of the air cylinder
device 80 to the driving force of the feed rod servomotor 74, even
when the bar material 200 has the dimeter of 40 mm or more, for
example, the feed rod 60 moves backward against the frictional
force (fitting force) between the finger chuck 61 and the bar
material 200. The bar material 200 is thereby released from the
finger chuck 61. After releasing the bar material 200, the fixation
of the bar material 200 by the fixing member is released, and the
air cylinder device 80 is disconnected from the chain 71.
[0021] The NC device 90 controls the operation of supplying one bar
material 200 from the stocked many bar materials 200 to the base 52
and the operation of the fixing member that controls the movement
of the bar material 200 in addition to the driving of the main
spindle servomotor 30, the feed rod servomotor 74, and the air
cylinder device 80 and the driving of the tool post 40 and a not
shown motor for rotating the main spindle 20. The NC device 90 is
disposed in a part of the automatic lathe main body 10, and
includes an input section 92 that inputs coded commands, a memory
93 that stores the input commands and various determination
standards, and a controller 94 that outputs control signals to the
automatic lathe main body 10 and the bar material supplying device
50 according to the commands.
[0022] The controller 94 compares a positional deviation (angle
deviation) between the positional command (rotation angle command
of feed rod servomotor 74) of the feed rod 60 to the feed rod
servomotor 74 and a feedback position (actual rotation angle of
operation amount of feed rod servomotor 74) of the feed rod 60 for
the feedback control of the servomotor with an allowable range of
an error of the operation amount as one of the determination
standard values stored in the memory 93, and determines the
existence or non-existence of an excessive error. When the
operation amount specified by the operation signals deviates from
the allowable range of the error, the controller 94 determines the
excessive error of the operation amount of the feed rod servomotor
74. The controller 94 stops the operation and displays the
excessive error on a display 91. When the operation amount
specified by the operation signals does not deviate from the
allowable range of the error, the controller 94 determines no
excessive error of the operation amount of the feed rod servomotor
74. The controller 94 continues the operation without stopping the
servomotor. Namely, the controller 94 constitutes one example of an
error allowable device that allows the error of the operation
amount of the feed rod servomotor 74 in the operation of inserting
and pulling the bar material 200 into and from the finger chuck 61.
The memory 93 stores a first allowable range that is an allowable
range of the error of the operation amount of the feed rod
servomotor 74 corresponding to the releasing and the chucking of
the bar material 200 and a second allowable range that is an
allowable range of the error of the operation amount of the feed
rod servomotor 74 corresponding to the normal back and forth
driving of the chain 71 only by the feed rod servomotor 74. The
first allowable range is set to be larger than the second allowable
range.
[0023] The controller 94 selects the first allowable range in the
chucking and the releasing, while the controller 94 selects the
second allowable range in the normal back and forth driving. More
specifically, when the command output to the bar material supplying
device 50 corresponds to the operation of chucking the bar material
200 and the operation of releasing the bar material 200, the first
allowable range is selected. When the command corresponds to an
operation except the operation of chucking and releasing, the
second allowable range is selected. The controller 94 compares the
selected first allowable range or second allowable range with the
above-described positional deviation (angle deviation).
[0024] The driving force of the chain 71 by the air cylinder device
80 is larger than the driving force of the chain 71 by the feed rod
servomotor 74, and the driving speed of the chain 71 by the air
cylinder device 80 is faster than the driving speed of the chain 71
by the feed rod servomotor 74. Consequently, when the air cylinder
device 80 drives the chain 71 in the chucking and the releasing of
the bar material 200, the feed rod servomotor 74 excessively
rotates along with the driving of the chain 71. The above-described
positional deviation (angle deviation) deviates from the second
allowable range, and the controller 94 determines the operation
error of the feed rod servomotor 74, so that the controller 94
stops the operation or displays the excessive error on the display
91.
[0025] In the automatic lathe 100 of the present embodiment, the
controller 94 selects the first allowable range in the chucking and
the releasing. With this configuration, although the feed rod
servomotor 74 deviates from the rotation angle to be originally
controlled due to the driving of the air cylinder device 80, when
the above-described positional deviation (angle deviation) is
within the first allowable range, the controller 94 determines no
error of the operation of the feed rod servomotor 74, continues the
operation without stopping the servomotor, and does not display the
excessive error on the display 91. The operation rate of the
automatic lathe 100 can be therefore improved.
[0026] The controller 94 rotates the feed rod servomotor 74 to
control the positional deviation when the above-described
positional deviation occurs. In this case, the driving current of
the feed rod servomotor 74 increases in accordance with an increase
in the positional deviation. The controller 94 stops the operation
as an error when the driving current of the feed rod servomotor 74
exceeds a predetermined limit value.
[0027] The controller 94 of the present embodiment includes a
current controller that controls the driving current of the feed
rod servomotor 74 not to exceed a predetermined value smaller than
the predetermined limit value. When the first allowable range is
selected, the driving current to the feed rod servomotor 74 does
not exceed the above-described predetermined value by operating the
current controller.
[0028] The error due to the excessive driving current is therefore
prevented, the feed rod servomotor 74 freely rotates in a range in
which the positional deviation is within the first allowable range,
and the bar material 200 is smoothly chucked and released by and
from the finger chuck 61. When the feed rod servomotor 74 rotates
in the range in which the positional deviation is within the first
allowable range, if the driving current of the feed rod servomotor
74 does not exceed the limit value, it is not always necessary to
operate the current controller. In the automatic lathe 100 of the
present embodiment, the NC device 90 that controls the automatic
lathe main body 10 is used as the control device of the present
invention. However, the present invention is not limited to the
above embodiment, and a control device dedicated for the bar
material supplying device can be used. The bar material supplying
device including such a control device dedicated for the bar
material supplying device is one example of the bar material
supplying device of the present embodiment.
CROSS-REFERENCE TO RELATED APPLICATION
[0029] The present application is based on and claims priority from
Japanese Patent Application No. 2013-192718, filed on Sep. 18,
2013, the disclosure of which is hereby incorporated by reference
in its entirety.
REFERENCE SIGNS LIST
[0030] 10 Automatic lathe main body [0031] 20 Main spindle [0032]
30 Main spindle servomotor [0033] 50 Bar material supplying device
[0034] 60 Feed rod [0035] 61 Finger chuck [0036] 71 Chain [0037] 74
Feed rod servomotor [0038] 80 Air cylinder device (cylinder device)
[0039] 90 NC device [0040] 100 Automatic lathe (Numerical control
machine tool) [0041] 200 Bar material
* * * * *